KR102556114B1 - Flame retardant polycarbonate resin composition, sheet and film using the same, and manufacturing method thereof - Google Patents

Abstract

According to the present invention, the polycarbonate resin (A) 73 to 94.5% by mass, the phosphorus-based flame retardant (B) 5 to 25% by mass, and the fluoropolymer (C) 0.1 to 2% by mass, the flow value at 280 ° C. A polycarbonate resin composition characterized by being 1×0.01 to 10×0.01 cm ³ /sec and a sheet/film using the same are provided.

Description

Flame retardant polycarbonate resin composition, sheet and film using the same, and manufacturing method thereof

The present invention relates to a flame retardant polycarbonate resin composition. In detail, it relates to a polycarbonate resin composition excellent in sheet-film moldability and excellent flame retardancy, a sheet and film using the same, and a method for producing the same.

BACKGROUND OF THE INVENTION Polycarbonate resins are widely used in a wide variety of fields because they have many excellent properties such as excellent heat resistance, mechanical properties and electrical properties, and high dimensional accuracy. For example, molded products by injection molding or extrusion molding of polycarbonate resin are used as automobile materials, electric and electronic device materials, housing materials, and materials for manufacturing parts in other industrial fields.

Among them, the flame retardant polycarbonate resin composition is used as a member of information and mobile devices such as computers, notebook personal computers, tablet terminals, smart phones and mobile phones, and OA equipment such as printers and copiers.

[0002] In recent years, miniaturization and thinning of electronic devices, including information and mobile devices as described above, are progressing. For the member to be used, a sheet/film having high flame retardancy such that it is VTM-2 or higher in the UL94 test is required even when the thickness is as thin as 0.25 mm or less.

For example, Patent Documents 1 and 2 describe a polycarbonate flame retardant resin composition using a phosphazene compound or a condensed phosphate ester compound as a flame retardant. However, this composition is mainly optimized for injection molding, and contains polyfluoroethylene having a low viscosity of the resin component, high shrinkage during molding, and poor dispersibility and a fibril-forming ability. However, it was unsuitable for the manufacture of sheets. That is, when the present composition is molded into a film sheet by the melt extrusion method, the unevenness of the thickness of the film sheet is large, and when the UL-94 VTM burning test is performed on a test piece having a thickness of 0.25 mm or less, the film during folding Since the rupture exceeded the mark, there was a problem of becoming unsuitable.

Patent Literature 3 describes a resin sheet obtained by blending polycarbonate with a phosphorus-based flame retardant and polyfluoroethylene. However, there is no description of the viscosity (flow value) of the resin composition in the text, and the composition of the examples includes a phosphorus-based flame retardant that enhances fluidity and fibrillated polyfluoroethylene that is poor in dispersibility in addition to the high fluidity of polycarbonate. Because of the additional blending, the thickness of the film/sheet obtained by the melt extrusion method is highly uneven, and this is also the case when a UL-94VTM burning test is performed on a test piece with a thickness of 0.25 mm or less, the tearing of the film during folding is beyond the mark. For this reason, there was a problem of incompatibility.

Japanese Unexamined Patent Publication No. 2013-224349 Japanese Unexamined Patent Publication No. 2011-057888 Japanese Unexamined Patent Publication No. 2005-200588

An object of the present invention is to provide a polycarbonate resin composition suitable for production of a film sheet having small thickness unevenness and excellent thin flame retardancy, and a sheet film using the same.

As a result of repeated studies to solve the above problems, the inventors of the present invention found that, by using a resin composition having a specific flow value composed of a mixture containing polycarbonate, a flame retardant, and a fluoropolymer, the flame retardancy is excellent and the thickness unevenness is small. It was discovered that a resin film/sheet could be provided. That is, this invention is shown below.

[1] 73 to 94.5% by mass of a polycarbonate resin (A), 5 to 25% by mass of a phosphorus-based flame retardant (B), and 0.1 to 2% by mass of a fluoropolymer (C), and a flow value at 280 ° C. of 1 × 0.01 to 10 × 0.01 cm ³ /sec polycarbonate resin composition, characterized in that.

[2] The polycarbonate resin composition according to [1], wherein the phosphorus-based flame retardant (B) is a phosphazene compound or a condensed phosphate ester.

[3] The polycarbonate resin composition according to [1] or [2], wherein the fluoropolymer (C) is a polymer or copolymer containing a tetrafluoroethylene structure.

[4] The polycarbonate resin composition according to any one of [1] to [3], wherein the polycarbonate resin (A) has a viscosity average molecular weight of 28,000 to 50,000.

[5] The polycarbonate resin composition according to any one of [1] to [4], for use in sheets or films.

[6] A sheet or film using the polycarbonate resin composition according to any one of [1] to [5].

[7] The sheet or film according to [6], having a thickness of 10 to 1000 µm.

[8] A method for producing a sheet or film including a step of extrusion molding the polycarbonate resin composition according to any one of [1] to [5].

[9] The fluoropolymer (C) is an uncoated particle made of a polymer or copolymer containing a tetrafluoroethylene structure, or a particle in which the polymer or copolymer is coated with a vinyl polymer, [1] - The polycarbonate resin composition according to any one of [5].

ADVANTAGE OF THE INVENTION According to the flame-retardant polycarbonate resin composition of this invention, the film sheet with few thickness unevenness and excellent flame retardancy is provided. Such a film/sheet can be suitably used as an insulating film for electronic and electric devices, a film for nameplates, and a film for housing bodies such as battery packs.

Hereinafter, the present invention will be described in detail. On the other hand, this invention is not limited to the following embodiment, In the range which does not deviate from the summary, it can change arbitrarily and can be implemented. On the other hand, all literature and publications described in this specification shall be incorporated into this specification in their entirety by reference regardless of their purpose. In addition, the disclosure of claims, specifications, drawings, and abstracts of Japanese Patent Application JP2015-171095 filed on August 31, 2015, which is the basis for claiming priority of this application, are incorporated herein by reference in their entirety.

[Polycarbonate Resin (A)]

The type of polycarbonate resin (A) used in the present invention (hereinafter sometimes referred to as "component (A)") is not particularly limited, but from the viewpoint of heat resistance and flame retardancy, the use of an aromatic polycarbonate resin is particularly preferable do. A polycarbonate resin is a thermoplastic polymer or copolymer which may be branched obtained by reacting a dihydroxy compound or a small amount of branching agent with phosgene or triphosgene or diester carbonate.

The method for producing the polycarbonate resin is not particularly limited, and those produced by a conventionally known phosgene method (interfacial polymerization method) or melt method (transesterification method) can be used. In the case of using the melting method, a polycarbonate resin having an adjusted amount of OH groups in the terminal groups can be used.

The proportion of the polycarbonate resin (A) in the polycarbonate resin composition (100% by mass) of the present invention is 73 to 94.5% by mass, preferably 80 to 94.5% by mass, more preferably 85 to 93% by mass from the viewpoint of heat resistance. do.

As the dihydroxy compound which is a raw material, 2,2-bis(4-hydroxyphenyl)propane (namely "bisphenol A"), tetramethylbisphenol A, bis(4-hydroxyphenyl)-p-diisopropylbenzene , hydroquinone, resorcinol, 4,4-dihydroxydiphenyl and the like. These may use 2 or more types together. Preferably, it is preferable to use bisphenol A as a main component from the viewpoint of heat resistance and availability. The polycarbonate resin whose main component is bisphenol A is one in which bisphenol A is used in an amount of 60 to 100 mol%, preferably 90 to 100 mol%, among the bisphenols used. In addition, a compound in which one or more tetraalkylphosphonium sulfonates are bonded to the above aromatic dihydroxy compound can also be used.

Moreover, a copolymer mainly composed of a polycarbonate resin, such as a copolymer of the dihydroxy compound and a compound having a siloxane structure, may be used.

In order to obtain a branched polycarbonate resin, a part of the dihydroxy compound described above may be substituted with a branching agent. Although it does not specifically limit as a branching agent, For example, phloroglucine, 4,6- dimethyl- 2,4,6- tri (4-hydroxyphenyl) hepten- 2,4,6- dimethyl- 2,4,6-tri (4-hydroxyphenyl) heptane, 2,6-dimethyl-2,4,6-tri (4-hydroxyphenyl) heptene-3, 1,3,5-tri ( Polyhydroxy compounds such as 4-hydroxyphenyl)benzene and 1,1,1-tri(4-hydroxyphenyl)ethane, 3,3-bis(4-hydroxyaryl)oxindole (i.e., “isatin bisphenol”), 5-chloroisatin, 5,7-dichloroisatin, 5-bromoisatin, and the like. The amount of these substituted compounds used is usually 0.01 to 10 mol%, preferably 0.1 to 2 mol%, based on the dihydroxy compound.

As the polycarbonate resin (A), among those described above, a polycarbonate resin derived from 2,2-bis(4-hydroxyphenyl)propane (ie, "bisphenol A") or a 2,2-bis(4- Polycarbonate copolymers derived from hydroxyphenyl)propane (ie "bisphenol A") and other aromatic dihydroxy compounds are preferred.

The above-mentioned polycarbonate resin may be used individually by 1 type, and may mix and use 2 or more types.

In order to adjust the molecular weight of the polycarbonate resin (A), a monovalent hydroxy compound such as an aromatic hydroxy compound may be used as the terminal terminator, and examples of the monovalent aromatic hydroxy compound include m- and p-methylphenol, m- and p-propylphenol, p-tert-butylphenol, and p-long chain alkyl substituted phenol.

In the present specification, the polycarbonate resin (A) refers to one having a viscosity average molecular weight [Mv] of 12,000 or more. A carbonate resin having a viscosity average molecular weight of less than 12,000 is referred to as a "carbonate oligomer" and is distinguished from the polycarbonate resin (A).

The molecular weight of the polycarbonate resin (A) used in the present invention is arbitrary depending on the application, and may be appropriately selected and determined mainly depending on the compounding ratio of the phosphorus-based flame retardant (B) and the fluoropolymer (C). From the viewpoints of moldability, strength of molded articles, etc., the molecular weight of the aromatic polycarbonate resin (A) is, in terms of viscosity average molecular weight [Mv], preferably 28,000 to 50,000, preferably 35,000 to 40,000. The molecular weight of the aromatic polycarbonate resin (A) is controlled by the amount of end terminator, polymerization time, and the like.

When the viscosity average molecular weight is 28,000 or more, the dispersibility of the fluoropolymer (C) in the polycarbonate resin (A) is improved, and the increase in the viscosity of the resin component suppresses shrinkage of the film ejected from the die due to the fluoropolymer. As a result, the unevenness in the thickness of the film/sheet is reduced, and the problem (insufficient flame retardancy) of the test piece being melted and cracked at the time of flame folding in the burning test of the thin film is prevented. When the viscosity average molecular weight is 30,000 or more, the dispersibility of the fluoropolymer (C) in the polycarbonate resin (A) is further improved, shrinkage of the film due to the fluoropolymer during molding is sufficiently suppressed, and thickness unevenness is reduced. A small film/sheet is obtained.

On the other hand, when the viscosity average molecular weight is 50,000 or less, the decrease in fluidity of the polycarbonate resin composition of the present invention can be suppressed, and the decrease in extrusion processability due to increase in screw torque, decrease in production rate, and additives due to increase in resin temperature problems such as deterioration can be suppressed.

Here, the viscosity average molecular weight [Mv] of the polycarbonate resin and the carbonate oligomer can be measured by the method described below.

<Viscosity average molecular weight (Mv) measurement conditions>

The viscosity average molecular weight [Mv] is calculated from the following Schnell's viscosity formula by obtaining the limiting viscosity [η] (unit dl/g) at a temperature of 20 ° C. using methylene chloride as a solvent and using an Uberhde viscometer. Mean value (viscosity average molecular weight: Mv).

Here, limiting viscosity [η] is a value calculated by measuring the specific viscosity [η _sp ] in each solution concentration [C] (g/dl) and calculating it by the following formula.

The polycarbonate resin composition of the present invention may contain a carbonate oligomer in addition to the polycarbonate resin (A). However, the carbonate oligomer may affect the fluidity and heat resistance of the resin composition. In order to improve the dispersibility of the fluoropolymer (C), suppress shrinkage during molding, and suppress a decrease in heat resistance of the resin composition, the lower the content of the carbonate oligomer, which is a low molecular weight component, is better. When the amount of the carbonate oligomer is large and/or the average molecular weight of the carbonate-based resin is small, the dispersibility of the fluoropolymer (C) deteriorates; shrinkage of the fluoropolymer during molding due to the low viscosity of the resin composition; and so on. For example, the blending amount of the carbonate oligomer relative to the total weight (100 parts by weight) of the polycarbonate resin (A) is preferably 0 to 3 parts by weight, more preferably 0 to 1 part by weight, still more preferably substantially 0 Part by weight, ie substantially free of carbonate oligomers, is preferred. The viscosity average molecular weight of the polycarbonate resin (A) and the carbonate-based resin component composed of the carbonate oligomer is preferably 28,000 to 50,000, preferably 35,000 to 40,000. In addition, the molecular weight distribution (Mw/Mn) of the polycarbonate resin (A) and the carbonate-based resin component composed of the carbonate oligomer is preferably 2.0 to 3.0, more preferably 2.4 to 2.8, particularly in view of fluidity and heat resistance. Preferably it is 2.4-2.7.

[Phosphorus flame retardant (B)]

The polycarbonate resin composition of the present invention contains a phosphorus-based flame retardant (B) to improve flame retardancy. The proportion of the phosphorus-based flame retardant (B) in the polycarbonate resin composition (100% by mass) is 5 to 25% by mass. Sufficient flame retardance can be provided as it is 5 mass % or more. If it is 25% by mass or less, the decrease in heat resistance of the resin composition can be suppressed. Moreover, 6-20 mass % is preferable and 7-15 mass % is more preferable at the point of balance of a flame retardance and heat resistance.

As the phosphorus-based flame retardant (B), a phosphate ester-based flame retardant, a phosphazene-based flame retardant, or the like can be used. Phosphorus flame retardant (B) may be used individually by 1 type, and may mix and use 2 or more types.

<Phosphoric acid ester flame retardant>

As the phosphorus-based flame retardant (B), a phosphoric acid ester-based flame retardant is preferably used because it has a high flame retardant effect and a fluidity improving effect. The phosphoric acid ester-based flame retardant is not limited, but as the phosphoric acid ester-based flame retardant, a phosphoric acid ester-based compound represented by the following general formula (IIa) is particularly preferable.

(In formula (IIa), R ¹ , R ² , R ³ and R ⁴ are each independently an alkyl group having 1 to 8 carbon atoms which may be substituted with an alkoxy group having 1 to 8 carbon atoms; or an alkyl group having 1 to 8 carbon atoms, or a carbon number represents an aryl group having 6 to 20 carbon atoms which may be substituted with a phenyl group which may be substituted with an alkyl group of 1 to 8; p, q, r and s are each independently 0 or 1, and t is an integer of 0 to 5 And, X represents an arylene group or a divalent group represented by the following formula (IIb).)

(In Formula (IIb), B is a single bond, -C(CH ₃ ) ₂ -, -SO ₂ -, -S- or -O-.)

In the formula (IIa), examples of the aryl group for R ¹ to ^{R 4} include a phenyl group and a naphthyl group. Moreover, as an arylene group of X, a phenylene group and a naphthylene group are mentioned. When t is 0, the compound represented by formula (IIa) is a phosphate ester, and when t is greater than 0, it is a condensed phosphate ester (including mixtures). In the present invention, condensed phosphoric acid esters are particularly suitably used.

As the phosphoric acid ester-based flame retardant represented by the formula (IIa), specifically, trimethyl phosphate, triethyl phosphate, tributyl phosphate, trioctyl phosphate, tributoxyethyl phosphate, triphenyl phosphate, tricresyl phosphate, tri Cresylphenyl Phosphate, Octyldiphenyl Phosphate, Diisopropylphenyl Phosphate, Bisphenol A Tetraphenyl Diphosphate, Bisphenol A Tetracresyl Diphosphate, Bisphenol A Tetraxylyl Diphosphate, Hydroquinone Tetraphenyl Diphosphate, Hydroquinone Tetracre Various things such as syl diphosphate, hydroquinone tetraxylyl diphosphate, resorcinol tetraphenyl diphosphate, and resorcinol bisdaixylenyl phosphate are exemplified. Among these, triphenyl phosphate, bisphenol A tetraphenyl diphosphate, resorcinol tetraphenyl diphosphate, resorcinol bisdi-2,6-xylenyl phosphate and the like are preferable. Examples of commercially available phosphate ester-based flame retardants include FP-600 manufactured by ADEKA Co., Ltd. and PX-200 manufactured by Daihachi Chemical Industry Co., Ltd.

The phosphoric acid ester type flame retardants mentioned above may be used individually by 1 type, or may be used in mixture of 2 or more types.

<Phosphazene flame retardant>

Phosphazene-based flame retardants are used as effective phosphorus-based flame retardants because they can suppress the decrease in heat resistance of the resin composition due to the addition of the flame retardant compared to phosphate ester-based flame retardants. The phosphazene-based flame retardant is an organic compound having a -P=N- bond in a molecule, and the phosphazene-based flame retardant is preferably a cyclic phosphazene compound represented by the following formula (IIIa) or a chain represented by the following formula (IIIb) and crosslinked phosphazene compounds formed by crosslinking at least one phosphazene compound selected from the group consisting of a phosphazene compound, the following formula (IIIa) and the following formula (IIIb) with a crosslinking group. As a crosslinked phosphazene compound, what is crosslinked by the crosslinking group represented by following formula (IIIc) is preferable from a flame retardant point.

(In formula (IIIa), m is an integer of 3 to 25, R ⁵ may be the same or different, and represents an aryl group or an alkylaryl group.)

(In formula (IIIb), n is an integer from 3 to 10,000, Z represents a -N=P(OR ⁵ ) ₃ group or a -N=P(O)OR ⁵ group, and Y is -P(OR ⁵ ) ₄ group or -P(O)(OR ⁵ ) ₂ group. R ⁵ may be the same or different and represent an aryl group or an alkylaryl group.)

(In formula (IIIc), A is -C(CH ₃ ) ₂ -, -SO ₂ -, -S- or -O-, and l is 0 or 1.)

Preferred examples of the cyclic and/or chain phosphazene compounds represented by formulas (IIIa) and (IIIb) are those in which R ⁵ is an aryl group having 6 to 20 carbon atoms which may be substituted with an alkyl group having 1 to 6 carbon atoms. can Specifically, cyclic or chain phosphazene compounds in which R ⁵ is an aryl group such as a phenyl group; R ⁵ is a tolyl group (o-, m-, p-tolyloxy group) or xylyl group (2,3-, 2,6-, 3,5-xylyl group) having 1 to 6 carbon atoms, preferably cyclic or chain phenoxyphosphazene which is an aryl group having 6 to 20 carbon atoms substituted with 1 to 3 alkyl; or cyclic or chain phenoxyphosphazene in which R ⁵ is combined. More specifically, phenoxyphosphazene, (poly)tolyloxyphosphazene (e.g. o-tolyloxyphosphazene, m-tolyloxyphosphazene, p-tolyloxyphosphazene, o,m-tolyloxyphosphazene , o,p-tolyloxyphosphazene, m,p-tolyloxyphosphazene, o,m,p-tolyloxyphosphazene, etc.), (poly)xylyloxyphosphazene, etc., and/or chain C _{1- 6} alkyl C _6-20 aryloxyphosphazene or (poly)phenoxytolyloxyphosphazene (eg, phenoxy o-tolyloxyphosphazene, phenoxy m-tolyloxyphosphazene, phenoxy p-tolyloxy phosphazene, phenoxy o,m-tolyloxyphosphazene, phenoxy o,p-tolyloxyphosphazene, phenoxy m,p-tolyloxyphosphazene, phenoxy o,m,p-tolyloxyphosphazene, etc.) , (poly) phenoxyxylyloxyphosphazene, (poly) phenoxytolyloxyxylyloxyphosphazene, and/or cyclic and/or chain C _6-20 aryl C _1-10 alkyl C _6-20 aryloxyphosphazene, etc. can be exemplified, preferably cyclic and/or chain phenoxyphosphazene, cyclic and/or chain C _1-3 alkyl C _6-20 aryloxyphosphazene, C _6-20 aryloxy C _1-3 alkyl C _6-20 aryloxyphosphazenes (eg, cyclic and/or chain tolyloxyphosphazenes, cyclic and/or chain phenoxytolylphenoxyphosphazenes, etc.). In addition, description of "C _1-6 " here means "of 1 to 6 carbon atoms", and the same applies to "C _6-20 ", "C _1-10 ", and the like. In addition, description of "(poly)phenoxy..." points out one or both of "phenoxy..." and "polyphenoxy...".

As the cyclic phosphazene compound represented by formula (IIIa), a cyclic phenoxyphosphazene in which R ⁵ is a phenyl group is particularly preferred. The cyclic phenoxyphosphazene compound is preferably a compound in which m in formula (IIIa) is an integer of 3 to 8, and may be a mixture of compounds having different m. Specifically, hexaphenoxycyclotriphosphazene (m=3 compound), octaphenoxycyclotetraphosphazene (m=4 compound), decapenoxycyclopentaphosphazene (m=5 compound), etc. or a mixture thereof. Especially, a mixture of compounds in which m = 3 is 50 mass% or more, m = 4 is 10 to 40 mass%, and m = 5 or more is 30 mass% or less in total is preferable.

Such a cyclic phenoxyphosphazene compound is, for example, hexachlorocyclotriphosphazene, octaphosphazene, octaphosphazene, hexachlorocyclotriphosphazene, etc. It can be produced by taking out cyclic chlorophosphazenes such as chlorocyclotetraphosphazene and decachlorocyclopentaphosphazene and substituting them with phenoxy groups.

As the chain phosphazene compound represented by formula (IIIb), chain phenoxyphosphazene in which R ⁵ is a phenyl group is particularly preferred. As such a chain phenoxyphosphazene compound, for example, a chloride of a cyclic phenoxyphosphazene compound obtained by the above method (for example, hexachlorocyclotriphosphazene) is subjected to ring-opening polymerization at a temperature of 220 to 250 ° C., and compounds obtained by substituting the obtained linear dichlorophosphazene having a polymerization degree of 3 to 10,000 with a phenoxy group. n in the formula (IIIb) of the linear phenoxyphosphazene compound is preferably 3 to 1,000, more preferably 3 to 100, still more preferably 3 to 25.

Examples of the crosslinked phenoxyphosphazene compound include a compound having a crosslinked structure of 4,4'-sulfonyldiphenylene (bisphenol S residue), 2,2-(4,4'-diphenylene)isopropyl 4,4'-diphenyl, such as a compound having a crosslinked structure of a leadene group, a compound having a crosslinked structure of a 4,4'-oxydiphenylene group, and a compound having a crosslinked structure of a 4,4'-thiodiphenylene group Compounds having a cross-linked structure of a rene group, and the like are exemplified.

Further, as the crosslinked phosphazene compound, a crosslinked phenoxyphosphazene compound obtained by crosslinking a cyclic phenoxyphosphazene compound in which R ⁵ is a phenyl group in the formula (IIIa) is crosslinked by a crosslinking group represented by the formula (IIIc), or the formula In (IIIb), a crosslinked phenoxyphosphazene compound obtained by crosslinking a chain phenoxyphosphazene compound in which R ⁵ is a phenyl group with a crosslinking group represented by the above formula (IIIc) is preferred in terms of flame retardance, and is a cyclic phenoxyphosphazene compound. A crosslinked phenoxyphosphazene compound obtained by crosslinking the compound by a crosslinking group represented by the formula (IIIc) is more preferred.

In addition, the content of phenylene groups in the crosslinked phenoxyphosphazene compound is based on the total number of phenyl groups and phenylene groups in the cyclic phosphazene compound represented by formula (IIIa) and/or the chain phenoxyphosphazene compound represented by formula (IIIb) As such, it is usually 50 to 99.9%, preferably 70 to 90%. In addition, it is particularly preferable that the crosslinked phenoxyphosphazene compound is a compound having no free hydroxyl group in its molecule.

In the present invention, the phosphazene-based flame retardant is a cyclic phenoxyphosphazene compound represented by the formula (IIIa) and a crosslinked phenoxy compound formed by crosslinking the cyclic phenoxyphosphazene compound represented by the formula (IIIa) by a crosslinking group. At least one selected from the group consisting of cyphosphazene compounds is preferred from the viewpoint of flame retardancy and mechanical properties. Examples of commercially available phosphazene-based flame retardants include "Rabitl FP-110" and "Rabitl FP-110T" manufactured by Fushimi Pharmaceutical Co., Ltd., which are cyclic phenoxyphosphazenes, and "SPS100" manufactured by Otsuka Chemical Co., Ltd. can

The above-mentioned phosphazene-based flame retardants may be used individually by 1 type, or may be used in mixture of 2 or more types.

[Fluoropolymer (C)]

The fluoropolymer (C) is added to prevent dripping of combustible materials in the polycarbonate resin composition of the present invention.

As a fluoropolymer, a fluoroolefin resin is mentioned, for example. Fluoroolefin resin is usually a polymer or copolymer containing a fluoroethylene structure. A polymer or copolymer containing a fluoroethylene structure is a polymer having a fluoroethylene structure (constitutive unit) as a main component, and specifically, the fluoroethylene structure (constitutive unit of fluoroethylene) constitutes a fluoropolymer. Preferably it is 40-100 mass % of the whole monomer unit, More preferably, it is 50-100 mass %, More preferably, it is 60-100 mass %. The number average molecular weight of polytetrafluoroethylene is not particularly limited, but is preferably 3,000,000 to tens of millions (for example, 3,000,000 to 90,000,000).

Specific examples include polydifluoroethylene resin, polytetrafluoroethylene resin, tetrafluoroethylene/hexafluoropropylene copolymer resin, and tetrafluoroethylene/perfluoroalkyl vinyl ether copolymer resin. Among them, polytetrafluoroethylene resin is preferably used in terms of flame retardancy. Further, from the viewpoint of the sagging prevention and suppression effect of the test piece, a fluoroethylene resin having fibril-forming ability is also preferably used. On the other hand, "fibril-forming ability" refers to the tendency of resins to bond to each other and become fibrous due to an external action such as shear force.

Examples of the fluoroethylene resin having fibril-forming ability include "Teflon (registered trademark) 6J" and "Teflon (registered trademark) 640J" manufactured by Mitsui DuPont Fluorochemical Co., Ltd., and Polyflon F series manufactured by Daikin Chemical Industry Co., Ltd. (For example, "Polyn F201L", "Polyn F103", "Polyn FA500B", "Polyn FA500H", etc.). In addition, as a commercial product of an aqueous dispersion of a fluoroethylene resin having fibril-forming ability, for example, "Teflon (registered trademark) 30J" and "Teflon (registered trademark) 31-JR" manufactured by Mitsui DuPont Fluorochemical Co., Ltd., "Fluon D-1" by Kin Chemical Industry Co., Ltd., etc. are mentioned.

The shape of the fluoropolymer (C) in the present invention is not particularly limited, but it is preferably in the form of fine particles.

In addition, a fluoroethylene polymer (modified polytetrafluoroethylene) having a multilayer structure in which a fluoroethylene polymer is coated with a polymer (vinyl polymer) obtained by polymerizing vinyl monomers can also be used. Such modified polyfluoroethylene is advantageous in terms of handling during raw material compounding. Specific examples of such modified polyfluoroethylene include polystyrene-fluoroethylene composites, polystyrene-acrylonitrile-fluoroethylene composites, polymethyl methacrylate-fluoroethylene composites, and polybutyl methacrylate-fluoroethylene composites. A composite etc. are mentioned, As a specific example, "Metablen A-3800" by Mitsubishi Rayon Co., Ltd., "Brenxex 449" by GE Specialty Chemicals Co., Ltd., etc. are mentioned. Among them, acrylic-modified polyfluoroethylene having a multilayer structure of a (meth)acrylic resin (eg, polymethyl methacrylate, polybutyl methacrylate, etc.) and a fluoroethylene resin is preferable.

The fluoropolymer (C) in one embodiment of the present invention is an uncoated particle made of a polymer or copolymer having a tetrafluoroethylene structure (i.e., non-core-shell uniform particles) or the polymer Alternatively, the copolymer is a particle coated with the vinyl-based polymer.

On the other hand, 1 type of fluoropolymer may be contained, and 2 or more types may be contained in arbitrary combinations and ratios.

The proportion of the fluoropolymer in the polycarbonate resin composition (100% by mass) of the present invention is 0.1 to 2% by mass. When the proportion of the fluoropolymer is less than 0.1% by mass, the effect of improving flame retardancy by the fluoropolymer may be insufficient, and when the proportion of the fluoropolymer exceeds 2% by mass, the polycarbonate resin composition is molded There is a possibility that a molded article may have poor appearance, uneven thickness, and a decrease in mechanical strength. The proportion of the fluoropolymer is more preferably 0.5 to 1% by mass in terms of flame retardancy, thickness unevenness, and appearance.

[Other Ingredients]

(other resin components)

The aromatic polycarbonate resin composition of the present invention may contain other resin components other than the polycarbonate resin (A) or the fluoropolymer (C) as the resin component, as long as the object of the present invention is not impaired. Examples of other resin components that can be blended include polystyrene resin, high impact polystyrene resin, hydrogenated polystyrene resin, polyacrylstyrene resin, ABS resin, AS resin, AES resin, ASA resin, SMA resin, and polyalkyl methacrylic acid. rate resin, polymethacryl methacrylate resin, polyphenylether resin, polycarbonate resin other than component (A), amorphous polyalkylene terephthalate resin, polyester resin, amorphous polyamide resin, poly-4- Methylpentene-1, cyclic polyolefin resin, amorphous polyarylate resin, polyether sulfone, etc. are mentioned.

(other additives)

The aromatic polycarbonate resin composition of the present invention may further contain various additives within a range not impairing the effects of the present invention. Examples of such additives include stabilizers, antioxidants, release agents, ultraviolet absorbers, dyes, antistatic agents, flame retardants, impact strength improvers, plasticizers, dispersants, antibacterial agents, inorganic fillers (silicate compounds, glass fibers, carbon fibers, etc.), and the like. there is. 1 type may contain these resin additives, and 2 or more types may be contained in arbitrary combinations and ratios.

[Method for producing polycarbonate resin composition]

The method for producing the polycarbonate resin composition of the present invention is not limited, and a known method for producing a polycarbonate resin composition can be widely employed.

For example, the polycarbonate resin (A) according to the present invention, the phosphorus-based flame retardant (B), the fluoropolymer (C), and other components to be blended as necessary, for example, in a tumbler, Henschel mixer, or super mixer After mixing in advance using various mixers such as the like, a method of melt-kneading with a mixer such as a Banbury mixer, a roll, a Brabender, a single-screw kneading extruder, a twin-screw kneading extruder, or a kneader is exemplified.

[Flow value of polycarbonate resin composition]

The polycarbonate resin composition of the present invention is characterized in that the flow value of the resin composition at 280°C is 1×0.01 to 10×0.01 cm ³ /sec. The flow value (Q value) here refers to a value measured by the method described in JIS K7210-1:2014 Annex JA. The measurement was performed using a flow tester CFD500D manufactured by Shimadzu Corporation, using a die with a hole diameter of 1.0 mm and a length of 10 mm, and the amount of molten resin discharged under the conditions of a test temperature of 280°C, a test force of 160 kg/cm ² , and a residual heat time of 420 seconds as flow values. (×0.01 cm ³ /sec).

If the flow value of the resin composition is lower than 1 × 0.01 cm ³ /sec, the fluidity is insufficient, so the torque during sheet/film melt extrusion increases, and there are problems such as a decrease in productivity and deterioration of additives and the like due to shear heat generation. Further, since flowability increases when the flow value is higher than 10 × 0.01 cm ³ /sec, the amount of shrinkage derived from the fluoropolymer of the film/sheet coming out of the extruder die cannot be suppressed, causing unevenness in the thickness of the film/sheet, and thin film There is a problem such that flame retardancy is not obtained because the test piece is melted and cracked at the time of flame bonding in the combustion test. The flow value of the resin composition is preferably 2 × 0.01 cm ³ /second or more in terms of film formability by the melt extrusion molding method. Further, the flow value of the resin composition is preferably 9×0.01 cm ³ /sec or less, and more preferably 8×0.01 cm ³ /sec or less, from the viewpoint of further reducing unevenness in the thickness of the sheet/film.

A flow value within the above range is suitable for production of a film/sheet by extrusion molding. That is, the inventors paid attention to the flow value of the resin composition, and found that the flow value is related to thickness nonuniformity and thin flame retardancy in the case of a thin layer. When the flow value of the resin composition is controlled within the above range, suppression of thickness nonuniformity and provision of flame retardancy in a thin layer material becomes possible. On the other hand, in conventional mold molding (injection molding), a resin composition having a flow value of 10 × 0.01 to 50 × 0.01 cm ³ /sec is generally used, and the range of the flow value is different from the range of the present invention. For example, Eupyron (registered trademark) H-4000, manufactured by Mitsubishi Engineering Plastics Co., Ltd., used for injection molding, has a flow value within the above range (10 × 0.01 to 50 × 0.01 cm ³ /sec). do.

The flow value of the polycarbonate resin composition can be adjusted within a desired range by controlling the blending ratio of the constituent components (A) to (C) or the type of the constituent components (A) to (C). For example, it can be adjusted to a desired range by controlling the following items.

1) Viscosity average molecular weight (Mv) of polycarbonate resin (A)

Generally, when Mv is increased, the flow value tends to decrease.

2) Mixing ratio of phosphorus-based flame retardant (B)

In general, as the content of the phosphorus-based flame retardant increases, the flow value increases.

3) Blending of carbonate resin components, viscosity average molecular weight (Mv)

Generally, when Mv is increased, the flow value tends to decrease.

In general, when the content of the carbonate oligomer, which is a low molecular weight component, is high, the flow value tends to increase.

[Method for molding polycarbonate resin composition]

The polycarbonate resin composition of the present invention can be molded into various shapes. In particular, by using the polycarbonate resin composition of the present invention, it is possible to provide a molded article having excellent flame retardancy in a thin wall, which was difficult with conventional polycarbonate resin compositions. Examples of application of the molded article of the present invention include parts such as electric and electronic devices, office-assistance devices, information terminal devices, mechanical parts, household appliances, vehicle parts, building members, various containers, leisure goods and miscellaneous goods, and lighting equipment. . Among these, the molded article of the present invention is particularly suitable for use in parts and nameplates of electrical and electronic equipment, OA equipment, information terminal equipment, household appliances, lighting equipment, etc., because of its excellent flame retardancy, and is , particularly suitable for use in sheet members. Among them, the polycarbonate resin composition of the present invention is suitably used for molding into sheets and films, and sheets and films having small thickness unevenness and excellent thin flame retardancy are obtained.

There is no particular limitation on the method of producing a sheet or film from the polycarbonate resin composition of the present invention, and for example, a molding method such as a melt extrusion molding method, a solution casting method, a blow molding method, or an inflation molding method can be used. Among them, the extrusion molding method is preferable from the viewpoint of continuous productivity. In one preferred embodiment, a method for producing a sheet or film includes a step of extruding a polycarbonate resin composition.

In the polycarbonate resin sheet and film in the present invention, an unreinforced thermoplastic resin layer may be laminated on one or both surfaces of the surface layer. That is, according to one aspect of the present invention, a laminated sheet or film having a thermoplastic resin layer on at least one side of a polycarbonate resin layer is provided. By doing in this way, favorable surface smoothness, glossiness, and impact resistance are obtained, and when printing is performed on the back side of the non-reinforced layer, a deep external appearance is obtained.

In addition, the thermoplastic resin to be laminated may contain various additives. Examples of such additives include stabilizers, antioxidants, release agents, ultraviolet absorbers, dyes, antistatic agents, flame retardants, impact strength improvers, plasticizers, dispersants, and antibacterial agents. 1 type may contain these resin additives, and 2 or more types may be contained in arbitrary combinations and ratios.

On the other hand, a "sheet" generally refers to a thin, flat product whose thickness is smaller than the length and width, and a "film" is a thin film having an arbitrarily limited maximum thickness and an extremely small thickness compared to the length and width. It is a flat product, usually supplied in the form of a roll. However, in this specification, "sheet" and "film" are not clearly distinguished, and both are used with the same meaning.

[Thickness of film sheet]

The thickness of the film or sheet (polycarbonate resin layer in the case of a laminate) obtained from the polycarbonate resin composition of the present invention is preferably in the range of 10 to 1000 μm, more preferably in the range of 30 to 500 μm, and preferably in the range of 30 to 200 μm. A range is more preferable. The film or sheet obtained from the polycarbonate resin composition of the present invention has small thickness unevenness.

Example

Hereinafter, the present invention will be described in more detail by showing examples. However, the present invention is not limited to the following examples, and can be implemented with arbitrary changes within a range not departing from the gist of the present invention.

<Measurement of flow value of resin composition>

The flow value (Q value) of the resin composition pellets was evaluated with reference to the method described in JIS K7210-1:2014 Annex JA. The measurement was performed using a flow tester CFD500D manufactured by Shimadzu Corporation, using a die with a hole diameter of 1.0 mm and a length of 10 mm, and the amount of molten resin discharged under the conditions of a test temperature of 280 ° C, a test force of 160 kg / cm ² and a residual heat time of 420 seconds as the flow value (×0.01 cm ³ /sec). On the other hand, in the table, it is expressed as "flow value".

<Measurement of thickness of resin film (film thickness distribution)>

The film thickness distribution of the resin film was measured using a contact-type tabletop offline thickness measuring device (TOF-5R) manufactured by Yamabun Electric Co., Ltd. The thickness of the central part of the film was measured at 10 mm intervals along the flow direction (MD direction) during extrusion molding at 140 points in total, and the average value and standard deviation of the film thickness were obtained to evaluate the variation in film thickness. On the other hand, in the tables, "average film thickness" and "film thickness standard deviation" are expressed. Regarding film thickness variation (thickness unevenness), a film thickness standard deviation of 0 μm or more and less than 2 μm is “very good”, 2 μm or more and less than 4 μm is “good”, and 4 μm or more is “poor”.

<Evaluation of flame retardancy>

The flame retardancy evaluation of the polycarbonate resin film was evaluated by a method based on the UL94/VTM burning test established by the US Underwriters Laboratories (UL) using a film cut to a width of 50 mm × length of 200 mm × thickness of 50 μm. . In this evaluation, from the criteria shown in Table 1 below, those judged as VTM-0 were considered acceptable, and those in which the deformation (melting rupture) of the test piece during stitching exceeded the marked line were considered unsuitable. On the other hand, in the table|surface, it describes as "UL94 flame retardance."

(Assessment Methods)

(i) Preparation of measurement sample

The measurement sample is cut to the above size (the width 50 mm × length 200 mm × thickness 50 μm).

A sample left for 48 hours at 23°C and 50%RH was sample A, and a sample left at a temperature of 70°C for 168 hours and then cooled for 4 hours at a temperature of 23°C and 20%RH or less was sample B, 5 samples each. Prepare as a set.

(ii) measurement method

A line is drawn in a direction parallel to the short side at a place 125 mm from the short side of each sample, and it is wrapped around a rod with a diameter of 12.7 mm so that the short side is in the vertical direction. After fixing the inside of the 75 mm part above the 125 mm mark with pressure-sensitive tape, pull out the rod. The top of the sample is kept closed to avoid chimney effect during the test. Next, each sample was set vertically, and a cotton pad was placed 300 mm below it. Using a Bunsen burner with a diameter of 9.5 mm and a flame length of 20 mm as a heating source, a blue flame is applied to the center of the lower end of the sample for 3 seconds so that the burner tube is located 10 mm from the lower end of the sample, and the first flame separation (離) The burning time (t1) after burning is measured. Then, as soon as the flame disappears, flame contact is performed again for 3 seconds, and the burning time (t2) after the second flame transfer is measured. Moreover, it is also observed whether there is a combustion falling object which ignites the absorbent cotton. With respect to sample A and sample B, the above measurement is performed one set (five sheets) each.

The one (t1 or t2) with the larger burning time after the 1st time (t1) or the 2nd time (t2) of each sample (t1 or t2) was evaluated as "the maximum burning time of each sample." The total burning time of 5 samples (sum of t1+t2 of 5 samples) was evaluated as "the total burning time of 5 samples". The presence or absence of a burning falling object that ignites the absorbent was evaluated as the presence or absence of "surface ignition by dripping".

[Materials used]

<Aromatic polycarbonate resin (A)>

(a-1) "Eupiron (registered trademark) K-4000F" manufactured by Mitsubishi Engineering Plastics Co., Ltd., bisphenol A type, viscosity average molecular weight 40,000, Mw/Mn = 2.7

(a-2) Mitsubishi Engineering Plastics Co., Ltd. "Eupilon (registered trademark) E-2000F", bisphenol A type, viscosity average molecular weight 28,000, Mw/Mn = 2.5

(a-3) Mitsubishi Engineering Plastics Co., Ltd. "Eupilon (registered trademark) S-3000F", bisphenol A type, viscosity average molecular weight 23,000

<Phosphorus flame retardant (B)>

(b-1) Phenoxyphosphazene (“Rabitl FP-110T” manufactured by Fushimi Pharmaceutical Co., Ltd.) (a compound in which m≥3 (main structure: cyclic trimer) and R ⁵ =phenyl group in the above formula (IIIa))

(b-2) Resorcinol bis-2,6-xyleneyl phosphate ("PX-200" manufactured by Daihachi Chemical Industry)

<Fluoropolymer (C)>

(c-1) Polytetrafluoroethylene having fibril-like performance (Polyflon "FA-500H" manufactured by Daikin Kogyo Co., Ltd.)

(c-2) Polytetrafluoroethylene coated with acrylic resin (polymethyl methacrylate), PTFE content 50% by mass (Metablen "A-3750" manufactured by Mitsubishi Rayon Co., Ltd.)

<Other additives (D)>

(d-1) Antioxidant: Pentaerythritol-tetrakis[3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate], (ADEKA Co., Ltd. Adekastab "AO -60”)

(d-2) Antioxidant: Tris (2,4-di-tert-butylphenyl) phosphite, (Adeka Staff "2112" manufactured by ADEKA Co., Ltd.)

[Examples 1 to 6, Comparative Examples 1 to 7]

<Manufacture of resin pellets>

A polycarbonate resin composition having the composition shown in Tables 2 and 3 was obtained as follows.

Using a twin-screw extruder TEX30α (C18 block, L/D = 55) manufactured by Nippon Steelworks Co., Ltd. equipped with one vent, each component was kneaded under the conditions of a screw rotation speed of 200 rpm, a discharge amount of 20 kg/hour, and a barrel temperature of 300 ° C. The molten resin extruded was rapidly cooled in a water bath and pelletized using a pelletizer. The flow values of the obtained pellets are shown in Tables 2 and 3.

<Manufacture of resin film>

From the pellets made of the polycarbonate resin composition obtained above, a film was obtained by extrusion molding as follows.

A film having a width of 25 cm × a length of 10 m × a thickness of 0.05 mm was obtained using a single screw extruder PSV-30 manufactured by Plaange Co., Ltd. under conditions of a cylinder temperature of 300 ° C, a die temperature of 300 ° C, a roll temperature of 110 ° C and a screw rotation speed of 30 rpm. . However, the roll temperature was set at 130°C for the case where the compounding amount of the phosphorus-based flame retardant was 2%. In addition, since the glass transition temperature of the resin composition is small about the compounding amount of phosphorus flame retardant of 32%, molding was performed by setting the roll temperature to 50 degreeC. The evaluation results (average film thickness, film thickness standard deviation, UL94 flame retardancy) of the obtained film are shown in Tables 2 and 3.

As shown in Table 2, the polycarbonate resin compositions of Examples contain 73 to 94.5% by mass of the polycarbonate resin (A), 5 to 25% by mass of the phosphorus flame retardant (B), and 0.1 to 2% by mass of the fluoropolymer (C). Including, the flow value at 280 ° C. is adjusted to 1 × 0.01 to 10 × 0.01 cm ³ /sec. The films produced from the polycarbonate resin compositions of these Examples were all excellent in flame retardancy and had small unevenness in thickness.

In contrast, as shown in Table 3, in Comparative Examples 1 to 4 using a polycarbonate resin composition having a flow value of more than 10 × 0.01 cm ³ /sec at 280 ° C., the unevenness of the thickness of the molded film was large. Further, Comparative Example 5 containing less phosphorus-based flame retardant (B) in the polycarbonate resin composition and Comparative Example 6 containing no fluoropolymer (C) resulted in inferior flame retardancy. Further, in Comparative Example 7 containing an excessive amount of fluoropolymer (C), the unevenness of the thickness of the molded film was large, so that the flame retardancy test could not be conducted either.

From the above, according to the polycarbonate resin composition containing the polycarbonate resin (A), the phosphorus-based flame retardant (B) and the fluoropolymer (C) in a predetermined range and having a specific flow value, the thickness unevenness is small and the thin flame retardancy is high. It was confirmed that an excellent film sheet could be manufactured.

Claims (8)

The resin composition contains 73 to 94.5% by mass of polycarbonate resin (A), 5 to 25% by mass of phosphorus-based flame retardant (B), and 0.1 to 2% by mass of fluoropolymer (C), and has a flow value at 280 ° C. is 1×0.01 to 10×0.01 cm ³ /sec, and the viscosity average molecular weight of the polycarbonate resin (A) is 35,000 to 50,000. According to claim 1,
The polycarbonate resin composition wherein the phosphorus-based flame retardant (B) is a phosphazene compound or a condensed phosphoric acid ester. According to claim 1,
A polycarbonate resin composition wherein the fluoropolymer (C) is a polymer or copolymer containing a tetrafluoroethylene structure. delete According to claim 1,
A polycarbonate resin composition for use in sheets or films. A sheet or film using the polycarbonate resin composition according to any one of claims 1 to 3 and 5. According to claim 6,
A sheet or film with a thickness of 10 to 1000 μm. A method for producing a sheet or film comprising a step of extruding the polycarbonate resin composition according to any one of claims 1 to 3 and 5.